Manufacture of compositions and articles containing plasticizable substances and new plasticizers



Patented May 3, 1938 UNITED STATES PATENT OFFICE MANUFACTURE OFCOMPOSITIONS AND AR- TICLES CONTAINING PLASTICIZABLE SUB- STANCES ANDNEW PLASTICIZERS Henry Dreyfus, London, England No Drawing. Originalapplication February 8,,

1934, Serial No. 710,347.

Divided and this application February 4, 1937, Serial No. 124,13 7 InGreat Britain February 17, 1933 v 11 Claims.

This invention relates to the manufacture of compositions and articlesmade of or containing plasticizable substances, such as derivatives ofcellulose and synthetic resins, and a new class of plasticizer, and thisapplication is a divisional 5 ymethanol), mono-,acetyl methylene glycol(oxymethyl acetate) or monochlor methanol, The

term methylene glycol residue includes residues in which one or morehydrogen atoms are substltuted, for example by halogen atoms. The 20termpolycarboxylic acids-is used to denote acids containing more thanone carboxyl group, and includes dicarboxylic acids oi the carbocyclicseries, for example phthalic acid and its substitution products, and ofthe aliphatic series for example succinic, malonic, glutaric, andtartaric 25 acids. r

The esters of the invention are new chemical substances, and are claimedin my co-pending application S. No. 710,347.

The esters may contain two identical methylene glycol residues, or twomethylene glycol residues which, without being identical, are similar inconstitution, for example methoxy-methyl and ethoxy-methyl. On the otherhand, the esters may contain two entirely different methylene glycolresidues, for example an .aikoxy-methylene and an acidyl-oxy-methyleneglycol residue.

Further, the ester may contain in addition to a methylene glycol residuea hydrocarbon residue 40 or a residue of a dihydric alcohol containingmore than one carbon atom, for example a substit'uted'or unsubstitutedresidue derivable from ethylene glycol or its monoesters or ethers bythe removal of one hydroxy group. In such com- 45 pounds the dihydricalcohol residue may or may not be similar in constitution to themethylene glycol residue.

The new esters may be made by reaction between a substituted methanol(which maybe re- 50 garded as a hydroxy compound of a methylene glycolresidue as defined above) or its equivalent and the acid, anhydride oracid halide. As

an example of an equivalent of a substituted methanol may be mentionedformaldehyde and 55 water which may be employed in place of thehypothetical methylene glycol. Another method of preparation of theesters is by reaction between a mono-halide of a methylene glycolresidue (in other words, a derivative of a halogenated meth- 60 anol)and a monoor dimetallic salt of the acid.

Another method is the partial hydrolysis of esters in which at least twocarboxyl groups in the polycarboxylic acid are esterified with methyleneglycol residues, or 'with a methylene glycol residue and a different andmore readily removable group. In a further method esters ofpolycarboxylic acids with a methylene glycol residue whichis itselffurther esterified with a group which is more easily removed bysaponification than is the methylene glycol residue from thepolycarboxylic acid maybe subjected to a regulated and partialhydrolysis.

As examples of esters containing simple oxymethylene glycol residues,reference may be made to oxy-methyl phthalicacid, obtainable fromphthalic anhydride, formaldehyde and water in the presence of a suitablecatalyst, for example hydrochloric acid gas, or by partial hydrolysis ofdl-(oxy-methyl) phthalate or mono-(acetox'y methyl) phthalate;di-(oxy-methyl) phthalate, obtainable by saponiflcation of di-(acetoxymethyl) phthalate; and of methyl-(oxy-methyl) phthalate obtainable bysaponification of methyl- (acetoxy-methyl) phthalate.

Esters containing alkoxy-methyl groups may be illustrated by referenceto mono-(methoxymethyl) phthalate obtainable from mono-chlor dimethylether and mono-sodium phthalatej di- (methoxy-methyl) phthalateobtainable from mono-chlor dimethyl ether and di-sodium phthalate;methoxy-methyl-(ethoxy methyl) phthalate obtainable from mono-chlormethyl ethyl ether and sodlum-(methoxy-methyl) phthalate; methyl-(methoxy-methyl)phthalate obtainable from mono-chlor methyl ether andsodium methyl phthalate; methoxy methyl (acetoxy-ethyl) phthalateobtainable from mono-chlor dimethyl ether and sodium-(acetoxy-ethyl)phthalate; ethoxy methyl-(acetoxy-ethyl) phthalate obtainable frommono-chlor-methyl ethyl ether and so? dium-(acetoxy-ethyl) phthalate;methoxy-methyl-(oxy-ethyl) phthalate obtainable from monochlor dimethylether and sodium-(oxy-ethyl) phthalate; and ethoxy-methyl-(oxy ethyl)phthalate obtainable from mono-chlor-methyl ethyl ether and sodium-(oxy-ethyl) phthalate.

Examples of esters containing acidyl-oxymethylene glycol residues are:mono-(acetoxymethyl) phthalate obtainable from mono-chlormethyl acetateand mono-sodium phthalate; di- (acetoxy-methyl) phthalate obtainable,from mono-chlor-methyl acetate and di-sodium phthalate;methyl-(acetoxy-methyl) phthalate obtainable from sodium methylphthalate and mono-chlor-methyl acetate; acetoxy-methyl- (acetoxy-ethyl)phthalate obtainablefrom monochlor-methyl acetate andsodium-(acetoxyethyl) ethyl) phthalate obtainable from mono-chlorphthalate; and acetoxy-methyl-(oxymethyl acetate and sodium-(oxy-ethyl)phthalate.

As indicated above, the esters may contain two different methyleneglycol residues. Among such compounds mention may be: made ofmethoxymethyl-(acetoxy-methyl) plithalate, obtainable frommono-chlor-methyl acetate and sodium- -(methoxy-methyl) phthalate, orfrom monochlor dimethyl ether and sodium-(acetoxymethyl) phthalate; andethoxy-methyl-(acetoxymethyl) phthalate obtainable from mono-chlormethylethyl ether and sodium-(acetoxy-methyl) phthalate, or frommono-chlor-methyl acetate and sodium-(ethoxy-methyl) phthalate. I

In the preceding examples the new class of plasticizers is illustratedwith particular reference to phthalic acid derivatives, since esters ofthis partial hydrolysis of esters as described. Esters containingalkylor aryl halogen substituted groups are not excluded and may in fact beof particular value for certain purposes, by reason of their halogencontent. Thus the presence of halogens in such compounds in generaltends to increase their resistance to fire, a property which is ofconsiderable value in compositions containing inflammable substancessuch as nitrocellulose.

Those esters are to be preferred which do not give an acid reaction evenafter long storage or use. Should it, however, appear desirable for somespecial purposes to make use of esters which are acid or may developacidity, anti-acid bodies, for example tetramethyl urea and similarallqlated amino bodies may with advantage be included in compositionscontaining the esters.

The invention includes the application of the new plasticizers generallyin the manufacture of articles or materials comprising celluloseacetate, nitrocellulose, synthetic resins and like plasticizablesubstances, for example by moulding, extrusion, evaporation of solvent,coagulation by liquid media, spreading or spraying methods, and includesproducts, materials-and compositions of matter which contain theplasticizers or in the manufacture of which the plasticizers are used,for example moulding powders, moulded or extruded articles, sheets,films, ribbons, filaments, artificial paper, artificial leather,splinterless glass, lacquers, varnishes, enamels and coatingcompositions generally, whether for application to fibrous ornon-fibrous materials.

The new esters are of particular value when the plasticizable materialcomprises an organic ester of cellulose, for example an ester such ascellulose formate, propionate, butyrate and particularly celluloseacetate, or an ether such as methyl, ethyl or benzyl cellulose. Thecellulose esters or ethers may be esterified or etherified to anydesired-degree, for instance I may employ cellulose acetates having anacetyl content lying between that of the triacetate and the diacetate,such as the esters obtainable by hydrolyzing or ripening a triacetate toan acetyl content in the neighbourhood of 58% combined acetic acid, ortill it becomes soluble in acetone. The cellulose derivative may haveany desired viscosity characteristics according to the purpose for whichit is to be employed. In the'production of lacquers and other coatingcompositions cellulose derivatives of relatively low viscosity maygenerally be used. Where, however, tensile strength is a desideratum inthe product, it is preferable to employ esters of high viscosity. Theproduction of such esters is described in U. S. Patent No. 1,708,787.

The products and compositions of the invention may contain natural orsynthetic resins, for example shellac, dammar, phenol aldehyde resins ofthe soluble fusible type whether in the Novolak or Resol stage, andsoluble fusible resins from other starting materials, for instance fromdiphenylol propane and formaldehyde or from other aldehydes, from ureaor thiourea and formaldehyde, and particularly synthetic resins of thepolymerized vinyl ester type, for example polymerized vinyl acetate.

Many of the compositions will naturally contain in addition to the newplasticizers and the plasticizable material volatile solvents or solventmixtures therefor. For example, liquid compositions containing celluloseacetate may contain acetone, methyl ethyl ketone, ethyl formate, dioxaneand other volatile solvents. High boiling solvents, for examplecyclohexanone, ethyl lactate, diacetone alcohol, benzyl alcohol andcyclohexanol may also be present. The compositions may contain latentsolvents for the cellulose derivative, for example ethyl alcohol, methylalcohol and other aliphatic alcohols of low molecular weight, ethyleneand methylene chloride and other aliphatic halogenated hydrocarbons.There may be present two or more latent solvents which together form asolvent mixture for the cellulose acetate, for example mixtures of ethylor methyl alcohols with ethylene or methylene dichlorides. Thecompositions may moreover contain diluents or non-solvents for thecellulose derivative, for example benzene, toluene or any of the threexylenes, cumene, cymene or other hydrocarbons of low, medium or highboiling point. For example, coating compositions may-contain in additionto plasticizable material and one or more of the new plasticizers, a lowboiling solvent for the material, a medium boiling non-solvent thereforwith or without additional high boiling solvents or plasticizers, forexample, glycerin, triacetin,

tributyl phosphate, triphenyl phosphate, tricresyl phosphate, dibutyltartrate, triphenylol propane .or a plasticizer of the sulphonamide orsulphonanilide series. 'Non-inflammators may also be present and thesemay themselves function as plasticizers, as do, for example, tri-bromacetanilide and other halogenated acidylated aromatic amines.

Solvents, latent solvents, diluents and nonsolvents for theplasticizable material may be employed in the manufacture even of solidproducts. For example in the manufacture of filaments, ribbons and thelike by evaporative processes, the dope will in general contain, inaddition to the plasticizable material and a relatively small proportionof plasticizer, a relatively large proportion of a volatile solventorsolvent mixture. The solvent mixture may comprise two or more latentsolvents which together form asolvent mixture and/or may containsuitable non-solvents, provided these are not present in sufficientquantity to cause precipitation of the plasticizable material at tooearly 9. stage in the evaporation. Dopes for the production offilaments,-

ribbons, films and the like by the wet process may also contain suchliquids, though in this case it is not of course necessary that themajor part of the solvent or solvent mixture should be volatile, theessential being that a sufiicient proportion of the solvent should beremovable by the coagulating medium.

The plasticizers may be introduced into the product, material orcomposition at any convenient stage in the manufacture thereof and byany convenient means. In the case of solid products formed from liquidcompositions or dopes, for example by extrusion, evaporation,coagulation by liquid media or by spreading, it may be convenient tointroduce the plasticizers into the dope directly or in solution orsuspension in a suitable liquid. In the manufacture of moulding powdersand the products made therefrom, the plasticizer may conveniently beintroduced in the process of malaxation or may be sprayed on to thecellulose derivative in the form of a sol'u- Example 1 A celluloseacetate plastic composition containing as plasticizerdi-(acetoxy-methyl)phthalate may be made up as follows. 30 parts of the di-(acetoxy-methyl) phthalate are dissolved in 120 parts of a 50:50 alcoholbenzene mixture, and the solution is thoroughly incorporated with 100parts of acetone soluble cellulose acetate; the incorporation iseffected by means of malaxating rollers, the solvent being removed byevaporation in the usual way. The plasticized mass thus produced may beemployed for the manufacture of moulded products of any desired form.

Example 2 A composition which may be employed for the formation oflacquers or insulating coatings is:-

Parts Cellulose aceta 60 Polymerized vinyl acetate 40 Methoxy methyl(ethoxy-methyl) phthalate- 35 Acetnne 500 Benzen 250 Alcohol 250 Example3 Another composition that is suitable for the formation of lacquersis:--

Example 4 The following composition is very suitable for producinghighly flexible films or coatings which may be used for covering rubberinsulated cables or the like:

Having described my invention, what I desire to secure by Letters Patentis 1. Compositions and articles containing plasticizable substances suchas stable cellulose derivatives and synthetic and natural resins andesters of polycarboxylic acids, said esters containing at least oneacylated methylene glycol residue linked as an alcohol radicle to theacid radicle;

2. Compositions and articles containing organic derivatives of celluloseand esters of polycarboxylic acids, said esters containing at least oneacylated methylene glycol residue linked as an alcohol radicle to theacid radicle.

3. Compositions and articles containing cellulose acetate and esters ofpolycarboxylic acids, said esters containing at least one acylatedmethylene glycolresidue linked as an alcohol radicle to the acidradicle.

4. Compositions and articles containing plasticizable synthetic resinsand esters of polycarboxylic acids, said esters containing at least oneacylated methylene glycol residue linked as an alcohol radicle to theacid radicle.

5. Compositions and articles containing vinyl synthetic resins andesters of polycarboxylic acids, said esters containing at leastoneacylated methylene glycol residue linked as an alcohol radicle to theacid radicle.

6. Compositions and articles containing organic derivatives of celluloseand esters of phthalic acid, said esters containing at least oneacylated methylene glycol residue linked as an alcohol radicle to theacid radicle.

7. Compositions and articles containing organic derivatives of celluloseand esters of polycarboxylic acids, said esters containing at least twomethylene glycol residues linked as alcohol radicles to the acidradicle, at least one of said methylene glycol residues being acylated.

8. Compositions and articles containing organic derivatives of celluloseand esters of phthalic acid, I said esters containing two methyleneglycol residues linked as alcohol radicles to the acid radicle, at leastone of said methylene glycol residues being acylated.

9. Compositions and articles containing cellulose acetate and esters ofphthalic acid, said I esters containing at least one acylated methyleneglycol residue linked as an alcohol radicle to the acid radicle.

10. Compositions and articles containing cellulose acetate and esters ofphthalic acid, said esters containing two identical acylated methyleneglycol residues linked as alcohol radicles to th acid radicle.

11. Compositions and articles containing cellulose acetatev and estersof phthalic acid said esters containing an acylated methylene glycolresidue and an alkyl group linked as alcohol radicles to the acidradicle.

HENRY DREYF'US.

